The present invention relates to a diamond tool for cutting, grinding or drilling workpieces such as brick, concrete, granite, marble, etc., and more particularly to a diamond tool comprising a plurality of segment type cutting tips circumferentially fixed on the wheel of the diamond tool, each of which has at least two diamond layers formed the same plane of the wheel of the diamond tool, and capable of cutting, grinding or drilling workpieces as forming at least two microscopic linear cutting grooves in the workpieces when cutting operation.
A prior art diamond tool 1 for cutting workpieces, as shown in FIGS. 1 to 3, comprises a steel wheel body 2 whose center hole is connected with a shaft of an electrical motor, and a plurality of cutting tips 4 fixed circumferentially on the steel wheel body 2. Here, the steel wheel body 2 has a plurality of discharge slots 3 formed between the cutting tips 4, which are gathering and discharging the minute chips generated from the workpiece during the cutting operation.
The cutting tips 4 are fabricated by mixing abrasive materials such as diamond particles, metal powder composing of cobalt, nickel, bronze, copper, etc., or resin or ceramic, and then by pressing the mixed materials in a predetermined mold, thereby forming the same, as shown in FIG. 2. Because the cutting tips 4 are manufactured from the mixture mentioned above, the diamond particles 8 are randomly distributed in the one of both outer sides and on the surfaces of the cutting tips 4, as shown in FIG. 3A.
When the prior art diamond tool 1 rotates to cut or grind the workpiece, both outer surfaces of each cutting tip 4 contacts with corresponding surface of the workpieces and forms a cutting slot 6, as shown in FIG. 3B.
According as the prior art diamond tool 1 rotates, the chips are produced in cutting slot 6 from the workpiece and gathered in the discharge slots 3 of the steel wheel body 2. Then, the chips gathered in the discharged slots 3 are discharged outside from the steel wheel body 2.
Therefore, the prior art diamond tool 1 can effectively cut, grind or drill the workpieces as the discharge slots 3 formed in the steel wheel discharge the minute chips from the cutting slot 6 to the outside of the workpiece. However, since the cutting tip shape of the prior art diamond tool is formed like a bar and it includes with a uniformly mixed composition, all the surfaces of the cutting tip 4 contact with the workpieces to cut, grind or drill. Especially, both the edges of an both outer surfaces contact with the side walls and the bottom of cutting slot 6 during the cutting operation are defaced faster than the center surface of the cutting tip.
Accordingly, the contacting area of the cutting tip is enlarged and also increases the resistance of workpieces 5, thereby decreasing the cutting rate and the life of the diamond tool. Further, since the chip size produced during the cutting operation is very minute, most of the chips are possibly remained in the cutting slot 6 of the workpieces 5 and prevents both outer surfaces of the cutting tip 4 from contacting to the workpiece, or the bottom of the cutting slot 6, thereby decreasing the cutting rate of the diamond tool.
Also, the prior art diamond tool has the disadvantages in that the minute chips discharged from cutting slot 6 are dispersed in the air, and causes the bad affects to the worker and the contamination of environment.
It is an object of the present invention to provide a diamond tool for cutting, grinding or drilling workpieces such as brick, concrete, granite, marble, etc., having segment type cutting tips comprising a plurality of diamond layer cutting tips, each of which at least two diamond layers are longitudinally disposed along the rotation direction of the tool to form at least two microscopic cutting grooves in the workpieces during cutting operation and thereby to cause portions of workpieces between the cutting grooves to be easily crushed by non-diamond portions of the diamond layer cutting tips to enhance cutting rate of the tool.
It is another object of the present invention to provide a diamond tool for an apparatus such as cutting saw machine, grinding wheel machine, and core drilling machine, having a structure in which a segment type cutting tip is able to produce cutting chips with relatively large sizes during cutting operation so that those chips are easily discharged outside with reducing the friction with the segment type cutting tip of the tool, thereby to increase cutting rate and to prevent the chips from dispersing in the air and causing a bad affects to a worker and the contamination of environment.
It is the other object of the present invention to provide a diamond tool for an apparatus such as cutting saw machine, grinding wheel machine, and core drilling machine, having segment type cutting tips comprising a plurality of diamond layer cutting tips, each of which diamond particles in diamond layer thereof are distributed in a given pattern to reduce the amount of diamond particles used and thereby reduce the manufacturing cost of tool.
To accomplish these objects, a diamond tool having segment type cutting tip for use in apparatus for cutting, grinding or drilling workpieces according to the present invention comprises a wheel body connected with a shaft of electric motor, and segment type cutting tip for cutting, grinding or drilling workpieces comprising a plurality of diamond layer cutting tips disposed at predetermined intervals along the circumference of wheel body, each of diamond layer cutting tips having at least two diamond layers longitudinally disposed parallel with the rotation direction of the tool in which diamond particles are included, and non-diamond portion disposed between the diamond layers in which diamond particles are not included.
In this embodiment of the present invention, the segment type cutting tip further includes a plurality of non-diamond layer cutting tips, each of which diamond particles are randomly distributed in one of both outer sides and surfaces thereof, and the non-diamond layer cutting tips and diamond layer cutting tips are alternatively disposed each other on the circumference of wheel body.
Further, diamond particles in each diamond layer of diamond layer cutting tips are distributed in a given pattern or arrangement such a single or double layer figure with grid shaped spots.
Also, in the non-diamond portion of each diamond layer cutting tip, diamond particles can be distributed in the density lower than that of diamond layers of diamond layer cutting tips or non-diamond layer cutting tips.
In another embodiment of the present invention, a diamond tool for cutting, grinding or drilling workpieces comprises a wheel body connected with a shaft of electric motor, and segment type cutting tip for cutting, grinding or drilling workpieces comprising a plurality of diamond layer cutting tips disposed at predetermined intervals on the circumference of wheel body, each of diamond layer cutting tips having non-diamond portion including a depressed portion disposed in the center of one of both outer surfaces thereof and cutting portions disposed in both edges of the other of both outer surfaces thereof, and a plurality of diamond layers longitudinally disposed parallel with the rotation direction of the tool respectively on bottom surfaces of cutting portions of non-diamond portion and both outer surfaces of non-diamond portion of diamond layer cutting tips divided or reduced by depressed portion and cutting portions thereof.
In this embodiment of the present invention, diamond layer cutting tips are disposed on the circumference of wheel body so that depressed portion and cutting portions thereof are alternatively directed to both outer sides.
Also, bottom surfaces of cutting portions of non-diamond portion are positioned in the plane forming the center between both outer surfaces of non-diamond portion of diamond layer cutting tips to let diamond layers disposed thereon to form one cutting line during the cutting operation of tool.
In other embodiment of the present invention, a diamond tool for use in apparatus for cutting, grinding or drilling workpieces comprises a wheel body connected with a shaft of electric motor, and segment type cutting tip for cutting, grinding or drilling workpieces comprising a plurality of diamond layer cutting tips disposed at predetermined intervals on the circumference of wheel body, each of diamond layer cutting tips having non-diamond portion including at least one depressed portion disposed in one of both outer surfaces or/and the other of both outer surfaces thereof, and a plurality of diamond layers longitudinally disposed parallel with the rotation direction of the tool respectively on bottom surface of depressed portion of non-diamond portion and one of both outer surfaces or/and the other of both outer surfaces of non-diamond portion of diamond layer cutting tips divided or/and not divided by depressed portion thereof.
In the embodiment of the present invention, diamond layer cutting tips have four both depressed portions which are disposed to cross each other at predetermined intervals in both outer surfaces thereof.
It is desirable that the depth of all bottom surfaces of depressed portions of both outer surfaces of non-diamond portion is a half of the thickness of diamond layer cutting tip to let diamond layers disposed thereon to form one linear cutting line during the cutting operation of tool.
However, the depth of bottom surfaces of depressed portions of each both outer surfaces of non-diamond portion can be less than a half of the thickness of non-diamond portion of diamond layer cutting tip to let diamond layers disposed thereon to form at least two linear cutting lines during the cutting operation of tool.